Question

I had a typed DataTable which to sort was just something like:

DataTable.DefaultView.Sort("sortexpression");

Because the sort expression was a string I could just append both the sort field and direction in a couple of lines, regardless of how many sort options I had. Now with Linq Im clearly doing something very wrong because to do something similar I’m doing this:

             this.GetSortExpressions();
        if ((ViewState["SortDirection"] as string) == "ASC")
        {
            switch (ViewState["SortField"] as string)
            {
                case "LKey":
                    this.SortedDetails = this.Details.OrderBy(d => d.LKey);
                    break;
                case "MName":
                    this.SortedDetails = this.Details.OrderBy(d => d.MaterialName);
                    break;
                case "FMSQOH":
                    this.SortedDetails = this.Details.OrderBy(d => d.FMSQOH);
                    break;
                case "CCQOH":
                    this.SortedDetails = this.Details.OrderBy(d => d.CCQOH);
                    break;
                case "FMSQOHVary":
                    this.SortedDetails = this.Details.OrderBy(d => d.FMSQOHVary);
                    break;
                default:
                    this.SortedDetails = this.Details.OrderBy(d => d.LKey);
                    break;
            }
        }
        else
        {
            switch (ViewState["SortField"] as string)
            {
                case "LKey":
                    this.SortedDetails = this.Details.OrderByDescending(d => d.LKey);
                    break;
                case "MName":
                    this.SortedDetails = this.Details.OrderByDescending(d => d.MaterialName);
                    break;
                case "FMSQOH":
                    this.SortedDetails = this.Details.OrderByDescending(d => d.FMSQOH);
                    break;
                case "CCQOH":
                    this.SortedDetails = this.Details.OrderByDescending(d => d.CCQOH);
                    break;
                case "FMSQOHVary":
                    this.SortedDetails = this.Details.OrderByDescending(d => d.FMSQOHVary);
                    break;
                default:
                    this.SortedDetails = this.Details.OrderByDescending(d => d.LKey);
                    break;
            }
        }

It’s god awful. I’m concerned about the fact that Im adding 2*n case statements for every new sort field. What is the right way please?

Answer 1

I have been gone through this.. what i found lastly was a generic solution that use reflection to sort a IEnumerable object.

http://zhousanfeng.wordpress.com/2009/12/01/a-generic-comparersorter-class%E8%BD%AC/

this will be how you could use it

Sorter<TestClass> sort = new Sorter<TestClass>(this.Deatils, "LKey ASC");
List<TestClass> sorted = sort.GetSortedList();

Regards.